Spectral analysis techniques have historically been used to characterize and quantify compositions of interest. A cost-effective way to utilize spectrophotometers for liquid samples is to use flow-through cells. However, it is difficult to design and mount flow-through cells for spectrophotometers that provide the necessary flow characteristics and ease of mounting necessary to successfully convert a spectrophotometer where samples are introduced manually via a cuvette to one where air-segmented samples may flow and be de-bubbled immediately prior to being introduced into the light path. This is evidenced by the fact that few vendors provide this technology for ultra-violet and visible wavelengths. The capability to use a flow-through cell would expand the marketability of any spectrophotometer that possessed it.
The prior art generally provides for spectrophotometric flow cell support devices. For example, U.S. Pat. No. 2,637,817 to Herbert provides for a positioning adaptor for an infrared spectroscopic cell which provides an adjustment mechanism for the length of the infrared path through the liquid being measured. The adjustment is limited to a linear change along one axis; further, no rotational change of cell orientation is possible. U.S. Pat. No. 2,864,279, to Phifer, discloses a spectrophotometer cell holder which does not allow for any adjustment of the cell position once mounted on the holder. U.S. Pat. No. 2,970,216, to Magrath, discloses a sample cell for spectroscopic apparatus which, like the Herbert device, permits only unidirectional, linear adjustment of the cell. None of these devices have the capability of providing multidirectionally and rotatably adjustable support for a conventional T-type flow-through cell.
It will accordingly be appreciated that there is a need for a flow cell support device which is manipulatable to adjust the position and orientation of a T-type flow-through cell which is utilized in modern spectrophotometry because of its higher resolution with lower dead volume.